Electric switch and handle



July 2l, 1925. 1,546,474

E. L. CONNELL.

ELECTRIC SWITCH AND HANDLE Filed Aug- 11, 1921 remita. .my-21d,- 192s.

L. A'ccnnmmsor Y r 1.546.474 PATENT OFFICE.

'nmac'rarc swrrcn ANDV HANDLE.

Application med August 11. 1921.

. i To all 'whom 'z't may concern.:

Be it knownthat EDWIN L; CoNrmIL, a

citizen of the United States of America, re-A siding at Cleveland, in the county of Ouyahoga and State of Ohio, has invented cer-- tam new and 'useful Improvements in Elec- 'tric Switches. and Handles, of which the following is a specification.

My invention relates to improvements in electric switch and handle of .the type- -adapted `foremployment with, manually controlled electric tools, and has for its object the provision -of a simple and .com-

pact construction adapted for the convenient handling of the electric` tool and for i its automatic control.

It is highly desirable, if not necessary in the employment of electric tools, that the power shall' fbe instantly, positively and automatically cut off, either at the will' of the operative upon releasing the controlling member, or upon its accidental release.

With a switching handle of this type, it

` also is desirable that it shall be positioned close to the tool, yet it must be so disposed as to be out' of the way and permit the'use of the tool at close quarters.'

My invention has proceededv with these features in view, and the present' improvements embody a switching handle vand switch disposed rearwardly of the tool and '-slightly at one side; the switchbeing of i ments.

Fig. 2 is an enlar ed fragmentary view in vertical section, getter illustrating the switch and handle construction, and

Fig. 3 I is an enlarged horizontal section taken on line 3 3, Fig. 2.

Throughout the several figures of the drawings I have employed the same character of reference to :indicate similar parts.

Upon referring to Fig. 1,' it will be seen that the rearwardly positioned handle portion lies withinthe contour of the as'sociated electric drill, except upon one side,

serial 1ro. 491,629.

whereonA a lcasing is provided for .the switch omo, AssIGNoR 'rorH van Domr mmc'rnrc 'rooL comm, or CLEVELAND, omo, A CORPORATION oF omo.

proper and -for bringing in the electric power connection.

The drill a may taken as typical of.V

various electric-tools adapted for manual control. At the rear or left of the drill .there is provided a removable casing Section c, secured in' place by screws b. This member preferably has an integral pistolgrip handle d having a gripping portion and a switch-containing chamber d. The latter is closed by an insulating base plate df', to which the connecting wlres e, e of the power circuit are attached.

The controlling switch, as best shown in Fig. 2,'comprises a pivoted switch lever f mounting a circuit-closing member f which..

is adapted to engage contacts g, g', and complete the gap in the circuit? The switch lever f is bifurcated and accommodates the controlling cam h which is mounted upon.

a common pivot pin i. This cam has two operative faces JL', h, alternatively engaging the spring-pressed roller f. When said roller is in contact with the upper face h of said cam, the switch lever is held in its open position against the stop j.

direction, or to the dotted line position, the roller will snap past `the point of the cam and, riding the, under face h, of said cam, will force the switch lever down to close the circuit between the contacts g, g', as also shown by dotted lines. A stop j also is provided for the cam.l

In order to control said switch both manually and automatically, a lever member or trigger c is pivoted at c within the handle and normally is maintained in its outward or full line position by the spring la. The shorter end of the trigger k is connected with the cam h by the link' Z, so that-the cam normally is maintained in its full linel position by thetension of spring Ze, acting through the trigger Ic and link Z. This insures the maintenance of an open circuit through the switch at all times that the trigger is not'retracted.

When the operative hats-placed the drill in its desired position, he merely closes his fingers .upon'the trigger and gripping portion of the tool handle, and thereby immediately actuates the cam, as above explained,

UponA -partially rotating the cam in a clockwise as lon as the switch is thus held closed,l Imme iately upon the intentional or accidental release of the trigger k, however, the spring lc reacts upon thev cam to rotate it to the full line position, and the springpressed roller rides the upper faceph of said cam, an almost instantly opens the circuit to the motor. Not only does this aord the most effective and prompt control of the tool, but, in addition, the apparatus is safeguarded against accident. y

It will be apprecatedthat the controlling, switch and containing handle are relatively eective in`use. Thus, it is seen that the handle is most eiciently positioned approximately in the axis of the tool and rearwardly thereof, or in line with drill so that it may best bev directed by the operative. The switch is disposed closelyhadjacent to but outside of the gripping portion of said handle and the controlled motor of the tool, but at one side of the structure; the other side of the structure being substantially flush and unbroken` so that the drill may be used in corners and angular structures without' Having now described the preferred embodiment of my invention, I claim as new and desire to secure by Letters Patent, both in specificand equivalent forms, the following:

1. In apparatus of the class described, the combination with a handle member,- of an associated trigger, a normally tensioned spring, and a controlled switch comprising a cam actuated by the trigger and spring, a switch arm and its coacting contact, and

means reacting upon the camfor openingv and closing the circuit between the switch arm and contact alternatively with the op.

erative position of the cam, substantially as f set forth. simple and are extremely convenient and EDWIN L. CONNELL. 

